The germ line is the tissue specialized for generation of gametes;it includes oocytes and sperm in addition to immature germ cells such as germline stem cells. The somatic tissues of the gonad are intimately linked with the correct development and health of the germ line. The germline tissue is of tremendous practical and scholarly significance. It may well be the ultimate source of stem cells for tissue replacement in diseased or injured individuals, and it impacts issues of both contraception and fertility. Therefore, germline biology is crucial for both medicine and agriculture. Major intellectual and technical advances have spurred new and exciting findings in germ cell research. This impressive progress derives from a range of studies in both vertebrates and invertebrates. It is therefore critical that researchers from diverse technical and academic arenas be brought together to share their insights and discoveries. This proposal seeks support for the sixth, seventh, and eighth of a biennial series of meetings held at Cold Spring Harbor Laboratory that has emerged as the premiere meeting for this field. The 2008 Germ Cells meeting will be held October 1-5, 2008 at the Cold Spring Harbor Laboratory, and subsequent meetings will be held in the fall of 2010 and 2012. This meeting series is intended to provide a public forum for discussion of all aspects of germ cell research, from specification of primordial germ cells in the early embryo to the function of gametes in adults. The meeting will embrace investigations of germ cells in diverse organisms, including model organisms and humans. We expect to attract 250-300 participants from around the world. There are no competing meetings of similar scope in this important research area. Eight broad topics have been chosen for platform presentations: Themes in Germ Cell Biology, Germ Line and Reprogramming, Germ Cell Patterning and Specification, Germ Cell Formation In Vitro, Germ Line Stem Cells, Epigenetic Regulation, Post-Transcriptional Regulation of Germ Cell Development, and Germline Programs. Each session will be organized and co-chaired by two experts in the field. Speakers generally will include the chairs plus one or two additional invited speakers for each session;the remainder will be selected from submitted abstracts. We will encourage platform presentations from young scientists. We will also ensure time for interactions between scientists, particularly during meals and in poster sessions. Project Narrative: Animals and plants are composed of two types of cells: the 'mortal'somatic cells, which form the body of the organism, and the 'immortal'germ cells, which produce the next generation. During development, precursor or primordial germ cells are created in the embryo, eventually to become mature germ cells - sperm or eggs. This international conference will cover the latest research in germ cell biology. A better understanding of these processes will help to tackle infertility in human beings and certain kinds of developmental defects in children, as well as improved plant and animal breeding for agriculture and livestock management.